David is currently present in the forest for training. During this time he is also looking for a chance to summon Zero and his new avatar. Even though he was not able to see anyone near him, he still knew that some people would be watching over him.
'Sigh, I need a powerful observation technique that would help me to find people like this who are hiding themselves around me. I did not want to expose my ability to create my avatars.'
David is thinking about buying a technique that would be helpful in this kind of situation. Even though using the passive technique which let him sense the Zen aura of other Guardians, these passive techniques did not have a long range and it can only help him when people wouldn't try to hide their aura.